The company says the maps, which identifies buildings and other man-made structures in 20 countries with a 5-meter resolution, could be used to improve Internet access for rural users and for research, including improving responses to natural disasters.

This undated photo provided by Facebook shows the server room at the company's data center in Prineville, Ore. The social media site announced on Monday that it had developed highly-detailed population density maps in 20 countries. It's an effort that could improve Internet access for users in rural and remote areas and possibly help agencies better respond to natural disasters, the company says.

Now, Facebook is using its own expertise in computer vision — the image-analysis technology that powers the social network’s photo tagging features — to create detailed maps of where people live and how factors such as population density impact their ability to connect to the Internet.

So far, the effort has yielded maps of 20 countries, particularly focusing on identifying buildings and other man-made structures in rural and remote areas.

A team of researchers from the group worked with the company’s data science, artificial intelligence, and machine learning teams to analyze 350 terabytes worth of images that covered 21.6 million square kilometers across all the countries.

“The basis of this stems from being able to have accurate models of where people in the world are," Yael Maguire, who oversees Facebook’s Connectivity Lab, told Fast Company. “The data that [already existed] was somewhat inadequate to build adequate models for where” newer technologies, such as drones and satellites could be use most efficiently.

Using computer vision techniques, the researchers were able to identify man-made structures, which they are using as a proxy for people living in a particular area.

They created the maps using a three-step process that first discarded images with large, non-man-made features, such as deserts, forests, and water, then detected whether a satellite image contained a building.

Lastly, the researchers “trained” a neural network using a relatively small number of images — about 8,000 — to identify buildings in other countries while filtering out areas that didn’t contain man-made structures. They then redistributed census count of local populations equally over the buildings identified by the computer.

“This method assumes equal population distribution per building within a census area, which we felt was the least error-prone method of obtaining population densities since it doesn't make any assumptions on the number of people per building and constrains systematic errors to within one census area,” wrote researchers Andreas Gros and Tobias Tiecke in the blog post.

In addition to using a relatively small number of images to train the network to recognize buildings, the effort also improves on the resolution of existing population density models. While many are currently at a resolution of 1 kilometer, Facebook’s model offers data at a resolution of 5 meters, the researchers note.

In addition to its own efforts to improve Internet connectivity, the company also plans to release its work to the public later this year, including releasing a combined population data set developed with researchers from the Center for International Earth Science Information Network at Columbia University.

The Facebook researchers say the mapping project could have a variety of uses in addition to improving how users in rural parts of the world go online. It could help validate census data, aid socioeconomic research, and be used to create risk assessments for natural disasters that could improve the response from agencies around the world. Making the project publicly available greatly improves the ways in which the tools can be used, one industry expert says.

“Data about human populations—whether farm output or population density—is costly and slow to obtain,” Mark Johnson, chief executive of Descartes Labs, which analyzes satellite imagery for the agriculture industry, told Fast Company. “The most exciting thing about Facebook's work is not just about the population density of today, but looking backwards to see trends and running this analysis as new, better satellite imagery is available."